CASSION FOUNDATION Underwater Bridge Construction!Spot the Fatal Mistake # construction
Key points Here are the key points from the audio transcription on underwater constructions:
Coffer Dam Construction: Engineers avoid working directly underwater by constructing a temporary dam called a coffer dam to remove water from the construction area.
Guide Piles and Sheet Piles: The construction process begins with erecting guide piles using a pile driving hammer machine, followed by driving interlocking sheet piles into the soil until they reach bedrock.
Vibration
Technique: The pile driving machine uses vibration, induced by counter-rotating
eccentric weights, to penetrate the soil effectively.
Geotechnical
Study: Before pumping out water, engineers conduct a geotechnical study, often
using a cone penetration test to assess soil strength and determine how deep
the sheet piles must be driven.
Water
Leakage Management: As water is pumped out, engineers must manage potential
water leakage between the sheet piles, which can occur due to differential
pressure. A double-layered coffer dam filled with granular material can help
resist this leakage.
Structural
Integrity: The inward collapse of the coffer dam can be prevented by erecting a
bracing frame structure alongside the sheet piles, which provides lateral support.
These points summarize the essential processes and considerations involved in
underwater construction as discussed in the audio.